In recent years, it has been a hot spot to use flow control technology to generate control capability similar to mechanical rudder. Taking the flying wing configuration as the research object, based on CFD and low speed wind tunnel test, the circulation control of airfoil and wing based on Coanda effect is studied, and the parameter influence law and control effect are given. The results show that: when the rear edge of the wing is opened with the corresponding slot, the control capability of the upper-surface blowing is similar to that of the mechanical rudder; the control capacity of pitch and roll is increased with the decreasing of jet height and the increasing of air pressure ratio, the pitching and rolling capacity increases first and then decreases; the control effect of circular Coanda surface is better than elliptical Coanda surface; the pitching and rolling control effect of the optimized circulation-control scheme in Ma=0.2 is not lower than that of the mechanical rudder, the corresponding flow flux is about 0.05~0.07 kg/s.

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The interfacial phenomenon between liqiuid iron and coke is important for determining the melting efficiency in the blast furnace iron-making process. In this study, the interaction observed in the case of the iron-carbon (Fe–C) melt on coke substrate was investigated using a high-temperature vacuum wettability test equipment. The Fe–C melt did not wet and spread on the coke substrate with different graphitization degrees (r0) at a high temperature of 1450℃. The contact angles changed from 124.5° to 105.3°, and the r0 increased from 9.30 to 50.00, thus indicating a nonwetting state. The deepening of graphitization decreased the contact angle. Thereby, increasing the contact area between liquid iron and the carbonaceous material, which facilitated carbon dissolution. The irregular movements of Fe–C melt were observed in situ during the wetting process. The horizontal force of the droplet caused by interfacial tension and the contact angle; the Marangoni convection owing to the gradient of carbon concentration; and the impulse force caused by the generation, aggregation, and release of SiO bubbles at the interface were attributed to the driving force.